ask: Recent blood test shows my RDW high, my BUN, Calcium & Tp low. Why?

Anon - Thank you for writing. We aren't able to provide medical diagnoses through this site, and the test results you provided could have multiple interpretations. A starting point to better understand your results is the non-profit consumer information site provided by multiple professional associations associated with clinical labs. The site is Lab Tests Online (dot) org and this is the link to the section on how to understand test results:
http://www.labtestsonline.org/understanding/index.html

These tests require a physician's order. Have you discussed the results with your doctor? Would you care to share additional information about your current health situation and other questions you may have? We'd be happy to assist you with information and resources but need more data from you.
Take care, Pat